This is a very interesting conundrum for the flight schools, that I hadn't thought of:

If the airlines are successful at getting the 121 FO minimums lowered, a huge number of instructors will leave the flight schools for the airlines,.........leaving the flight schools without instructors,.......which will make it difficult for the flight schools to attract students,............ which means they won't be able to attract instructors,...... and the cycle continues.

Wash, rinse, repeat.